This invention relates to a Hall sensor formed in a semiconductor die and more particularly to such a die having layered pole pieces of high magnetic permeability deposited on the opposite major surfaces of the die.
Several known magnetic tape reading heads include a thin semiconductor Hall element sandwiched between two high-magnetic-permeability blocks serving as pole pieces. The semiconductor body is typically a III-V compound such as indium antimonide and only the Hall element is included there. Such materials make Hall elements of high sensitivity as magnetic field sensors but also of high sensitivity to physical stress, vibration and temperature.
It is therefore an object of this invention to provide a Hall sensor that is less sensitive to physical stress, vibration and temprature.
It is a further object of this invention to provide such a sensor wherein the Hall element is formed in a semiconductor die in which may also be integrated a Hall element voltage amplifier.
It is yet a further object of this invention to provide such a Hall element having intimately integrated therewith a pair of magnetic pole pieces.
It is another object of this invention to provide a high resolution magnetic-reading head for use with magnetic tapes, discs and the like.